markomarko
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Scissor truss question
- Thread starter markomarko
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mike93lx
ALLIANCE MEMBER
There shouldn't be, AFAIK.
You may know this already, but you have to balloon frame that end wall. You can't do a flat top plate then use short studs to tie into the truss
Do this
Not this
www.sbcacomponents.com
You may know this already, but you have to balloon frame that end wall. You can't do a flat top plate then use short studs to tie into the truss
Do this
Not this
There's a Better Way - Structural Building Components Association
Why flat-bottomed gable frames are not always the best solution
www.sbcacomponents.com
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markomarko
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Yes that is what I’m expecting to do. I just wasn’t sure what that was on the engineering they sent me. It was throwing me off.
mike93lx
ALLIANCE MEMBER
It doesn't have a call out for a part number, so I suspect it's there for dimensioning the width
CraigStu
Well-known member
Why would there be a scissor truss on the end wall. Seems like a standard truss matching the roof line and a standard wall would be a he11 of a lot easier.
micromind
Well-known member
I would specify basic gable trusses for the ends. No need to frame under them and the wall bears the load, not the truss.
mike93lx
ALLIANCE MEMBER
That makes it hard to properly brace the trusses and tie in the ceiling. Check out the link I provided above.
The Gable framing needs to match the ceiling profile
larry4406
Well-known member
Hinge in the gable wall is best avoided....
Firebrick43
Well-known member
Because its against code in most places creating a failure hinge. This explains why
Sounds like a great idea, if you like a floppy weak wall.
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markomarko
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Another thing I just thought of. If I balloon frame, what’s keeping the exterior walls from kicking out since there’s no double top plate under the scissor truss?
Huh?
Double top plate isn't about walls kicking out, it's about proper load transfer from roof to wall framing.
You have 8+ feet of 2x material continuously framed up and attached to the truss, which is tied back to the rest of the roof trusses. Why would the wall "kick out"?
mike93lx
ALLIANCE MEMBER
And there is almost no downward load on that wall.
@markomarko it feels like you are getting way ahead of yourself on this build. You have trusses showing up but don't know how to frame the walls. How was the building designed?
micromind
Well-known member
Once the plywood is on the outside and the 2X4 runners are installed on the trusses, it's actually a pretty solid wall.
His other thread
Thread 'Zip R6 on gable end with overhang' https://www.garagejournal.com/forum/threads/zip-r6-on-gable-end-with-overhang.559324/
Firebrick43
Well-known member
The ceiling does or if no ceiling, the bottom chord bracing.
CraigStu
Well-known member
Thanks Firebrick43.
firebirdparts
Well-known member
That’s not a truss pictured, so it’s very weak. That is why you need that brace.
Just to be clear, I am intending my response to be on topic. I am not making commentary on balloon framing but rather delivery
Just to be clear, I am intending my response to be on topic. I am not making commentary on balloon framing but rather delivery
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markomarko
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Thank you for all the reply guys. Me and my friend put up all my standard trusses today. I framed out the gable end rake. I ended up doubling up the 2x on the gable end overhang so the r6 will **** up to it and then the next set of 2x for the overhang will be able to catch the vinyl soffit.
My friend and I will be putting up the scissor trusses tomorrow. We did everything just the two of us with a third friend helping out halfway through the day. The first gable end was very heavy to lift but it’s all set.
My friend and I will be putting up the scissor trusses tomorrow. We did everything just the two of us with a third friend helping out halfway through the day. The first gable end was very heavy to lift but it’s all set.
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mike93lx
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How are you transitioning to the scissor truss? Laying one against the standard, adding blocking to the standard or something else?
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markomarko
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We are going to figure that out this morning. Any recommendations?
mike93lx
ALLIANCE MEMBER
It's not in the truss plan?
If they didn't include one for that purpose, I think you're installing blocking
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markomarko
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It is not in the truss plan. We only received center and gable trusses.
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mike93lx
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Looks like it's time for blocking.
I'd use the same size lumber as the bottom chord of the scissor truss and mount it, aligned with the scissor truss bottom chord, to the standard truss. Tie in the bracing to that.
I'd use the same size lumber as the bottom chord of the scissor truss and mount it, aligned with the scissor truss bottom chord, to the standard truss. Tie in the bracing to that.
That was a nice reference.
This image seems to suggest that the ceiling diaphragm is a structural elelment?
Thanks, Alan
This
Firebrick43
Well-known member
The ceiling is very much a part the system.
Bracing can be used in lieu of the ceiling diaphragm if properly placed on the lower chords. There should be a bracing diagram with the trusses unless you told the engineer you were putting in a ceiling
Bracing can be used in lieu of the ceiling diaphragm if properly placed on the lower chords. There should be a bracing diagram with the trusses unless you told the engineer you were putting in a ceiling
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markomarko
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The part circled in red is to help the truss designer with layout, it's likely that it should have been deleted from the end drawing.